Adjustable anchorage



Jan- 20, 1953 E. A BLACK ADJUSTABLE ANCHORAGE Filed O01. 25, 1945 2 SHEETS-SHEET l w IIIIIIIIIA m.. 1.. .4. ,..I l

. INVENTOR smc; A. BLACK Jan. 20, 1953 E, A BLACK 2,625,815

ADJUSTABLE ANCHORAGE Filed OCT.. 25, 1943 2 SHEETS- SHEET 2 IN VEN TOR.

ERIC A. BLACK Patented Jan. 20, 1953 UNITED sTArgs egress* orties ADJUSTABLE ANCHORAGE Eric A. Black, Red Bank, N. J.

Application October 23, 1943, Serial No. 507,356

14 Claims. (Cl. 'Z2-77) (Granted under Title 35, U. S. Code (1952), sec. 266).

The invention described herein may be manufactured and used by and for the Government for governmental purposes, Without the payment to me of any royalty thereon.

This invention relates to anchorages for adjustably sustaining structures such as towers, buildings, bridges, and the like.

It is important that certain structures be so constructed that they may always be maintained exactly level. Hence, an adjustable anchorage is advisable. Such anchorages are particularly useful vin towers for some types of directional antennae. 1

In installing anchorages, a usual practice is to pour the rough concrete of the foundation columns or pedestals a little below the required height and then iix the exact height with ne plastic cement and screed angles or the like. After the plastic cement has hardened, grout is used to build up to the height so fixed. In this way the foundation may be made exactly level. However, if the foundation settles later, all this work is undone. My adjustable anchorage makes it possible to eliminate the` use of plastic cement and screed angles and to proceed with construction without waiting for plastic cement and later the grout to harden and if at any time the structure should not be exactly level, either because the foundation was not built exactly level originally Aor because it settled later, it may be readily corrected.

An object of the present invention is to provide an adjustable anchorage which, while having ample structural strength, nevertheless may be simply and quickly adjusted.

Another object is to provide such an anchorage which will so distribute the stresses that the size of a foundation may be safely reduced.

A further object is to provide an adjustable anchorage which will operate satisfactorily irrespective of weather, and the operating parts of which will remain free of dirt and moisture.

Another object is to reduce the construction time, materials and labor ordinarily necessary in building foundations.

Additional objects will appear from the following description.

In the drawings:

Figure l is an isometric view' of an adjustable anchorage, embodying the'present invention, in

use at the base of a wooden radio antenna tower; Figure 2 is a cross sectioned front view of the anchorage of Figure 1;

Figure 3 is an enlarged perspective of the upper @ne '0f the ySleeve 0f Figure .2:

Figure 4 is an enlarged isometric View of the strap plate of Figure l;

Figure 5 is an enlarged cross sectioned left side view of the weather-proof gasket and wedge of Figure 1;

Figure 6 is a horizontal section, along the line @-6 of Figure 5;

Figure 7 is an enlarged cross section o the lower end of the shaft of Figure 2; showing the wedge slots and part of the lubrication system;

Figure 8 is an enlarged sectioned side View of the anchor plate of Figure 2;

Figure 9 is a side elevation of my adjustable anchorage in use with a metal I beam; and

Figure 10 is a sectioned side view of a simplied form of my adjustable anchorage.

Figures 1 through 8 of the drawings show my adjustable anchorage in use at the base of a fourlegged, wooden, radio antenna tower (only one leg being shown). Each leg I6 is anchored to a concrete foundation column I5 by means of two of my adjustable anchorages, eight such anchorages being used for the entire structure. In Figure 1, one anchorage may be seen, another being on the far side of leg I6.

Referring now to Figures 1 through 8, and particularly to Figure 2, a preferred form of my adjustable anchorage comprises two main cooperating parts, the lower stationary male member A and the upper movable female member B.

The male member A (see Figure 2) is an elongated cylindrical anchor rod 8, which, at its upper end portion 24, is of a greater diameter. Said anchor rod 8 is threaded throughout said wider portion 24 and also at its lower end 23. vThe lower end of said anchor rod 8 is provided with a pair of hexagonal nuts l0 and Il, the upper nut l0 being welded to the rod 3 and the lower nut ll being fitted with a Cotter pin 3l. The

lower end of anchor rod extends through a hole in a steel anchor plate 9, being fastened thereto by the two nuts i9 and ll. Said anchor plate 9 is large enough so that the two adjustable an'- chorages, attached to lone leg I6 of the tower, may be fastened to it (see Figures 2 and 8). -To prevent rotation of the anchor rod 8, a'locking plate 32, abutting one of the flats of nut Il, is bolted to the under side of the anchor plate 9 by means of bolts 33. The anchorplateV 9 and the lower portion of anchor rod 8 are solidlyem beddedin the concretev column I5. Y,

The female member B (see -Figure 2) comprises a sleeve 1, which isan internally-threaded steel tube, and the shaft 20, which is a steel shaft threaded at both ends. The sleeve 'i and shaft 2i) are threadably coupled and then permanently welded together so as to form a unit. To facilitate and insure a good weld, the upper end of sleeve l has two longitudinal slots 34 (see Figure 3). The sleeve l and the upper end 22 of the anchor rod 8 are in operable threaded engagement. The lower end of sleeve 'l' is closed by a washer 38, which is held in place on the sleeve l by several machine screws 39.

The upper threaded end of shaft 2b is fitted with a square washer 26 and a pair of hexagonal nuts 2 and 3. The upper nut 2 is pierced by a transverse hole 36 and the upper end of shaft 2d is similarly pierced by a transverse hole I. When the nut 2 is raised so that these holes I and 35 are in register, a cylindrical steel pin (not shown), having a length equal to the flat-to-fiat diameter of nut 2, may be inserted through both holes to thereby lock said nut and shaft together, whence the shaft may be rotated by using a wrench on the nut. The lower portion of shaft 2li is pierced axially by a lubrication channel 35 (see Figure 7), into which lead several transverse threaded openings 35, pro-vided with Alemite type lubrication ttings 2 I. The shaft 20 has two trapezoidally-shaped, shallow slots 5l (see Figures 5, 6, and 7), on opposite sides of the shaft, to accommodate a wedge 22. Said wedge 22 is a U-shaped metal strap, each arm of which has its upper edge cut off at an angle so as to form a .f

wedge. (See Figures 5 and 6).

The shaft extends through a vertical channel di, formed by a loop 25 in a steel strap plate i8, said channel being a loose fit about said shaft 20 (see Figures l, 2, and 4). The loop 25 is cut oi at its lower end to expose the lubrication ttings 2I and the wedge 22. Said strap plate I8 is fastened to the wooden leg I6 of the antenna tower by means of bolts which also extend through an identical strap plate I8, on the opposite side of the leg. The bottom of the leg I5 rests upon a flat metal base plate I2, which has a hole 44 to freely accommodate shaft 20. To the lower surface of said base plate I2, coaxial with hole 44, is Welded a short tubular collar 3, which ts down into a cylindrical recess 41 in the concrete column I5, and is vertically movable in said recess. Said base plate I2 rests upon an annular, ball-type, thrust bearing 29, which encircles shaft 2i), and which bearing in turn rests upon the ulJ- :5f

per end of the sleeve 1. For protecting the anchorage mechanism and providing room to allow some transverse play thereof, a pipe 28 is solidly embedded in a cylindrical recess in the concrete, the diameter of said pipe being less than that of collar I3 but greater than that of the sleeve 'I.

In order to keep water and dirt from entering the hole 44 in the base plate I2 and seeping into the working parts, there is a weather-proof, annular gasket I9, of L-shaped cross-section (see Figure 5) surrounding shaft 25 and resting on the base plate. Said gasket I 9 is held in place by a split adjustable clamp 21, of similar cross-section, which is forced downward by means of the U-shaped wedge 22 which ts into the wedge slots 3l.

Gusset plates 52, for holding diagonal braces I? of the tower, are welded to two adjacent sides of the base plate I 2 (see Figure 1).

The threaded connection between the sleeve l and the anchor rod 8 is kept lubricated by means of the lubrication fitting 2I, the lubricant dropping down through the channel 30. The anchor rod B is kept from being accidentally unscrewed from the sleeve I by the washer 38.

My adjustable anchorage may also be used on a metal tower, one construction being indicated in Figure 9, where the shaft 20 extends through two holes cut in the flanges of a metal I beam d5. In this arrangement, the collar I3 (not shown in Figure 9, but see Figure 10 for similar construction) is welded directly to the under surface of the I beam 46, no separate base plate being necessary. The other parts are similar to those already described and shown in Figures 1 through 8 except that the strap plate I8, the bolts 45, the washer 25 and the base plate I2 are not needed in this construction.

To adjust my anchorage shown in Figures l through 9, the wedge 22 is removed, and the clamp 2l and the nuts 2 and 3 are loosened. The nut 2 is raised until hole 36 in the nut is in register with hole I in the shaft 20. The cylindrical steel pin, already described, is then inserted through the holes I and 36 so that the shaft 20 may be rotated by means of a Wrench on nut 2. The sleeve l, being integral with the shaft ZIB, will thus be caused to rotate. As the anchor rod 8 is immovably embedded in the concrete column I5, the rotation of the sleeve 'I will cause said sleeve to move vertically, thereby causing the thrust bearing 25, the base plate l2, and the leg I6 of the tower (it will be the I-beam 46 in the construction shown in Figure 9) to move with it. After adjustment, the steel pin is removed and the nuts 3 and 2 are retightened. The wedge 22 and the clamp 2l are then reinstalled and retightened. After the concrete columns I5 have settled and final adjustment of the anchorages has been made, any space between the concrete column I5 and base plate (or the I-beam 46 in Figure 9) may be lled in with a suitable shimming means, such as grout 133, so that the concrete column I5 directly receives part of the compressive load.

It is good practice to install a drainage tube (not shown) from the inside of the pipe 28, through the wall of the lower end of said pipe 28 and the concrete columns I5, so as to allow any water, which may possibly get into the pipe 28, to drain off. However, even should some water accumulate inside pipe 23, it will not affect the operation of the anchorage because the movable parts are grease packed. Even should some ice form within pipe 28, the movable parts will still be operable as the sleeve 'I (Figure 3) is cylindrical and may therefore rotate within the ice.

A simplied form of my adjustable anchorage, suitable for light work, is shown in Figure 10, where it is used to anchor a wooden tower. Fastened to the tower leg I6, by bolts d3, is a short length of Ushaped channel steel 5I. Both flanges 53 and 55 of the channel steel 5I have apertures to accommodate the cylindrical anchor rod 5l. Welded to the under surface of the lower flange 55 is a short tubular collar I3 which is, vertically slidable in a cylindrical recess "Il in the concrete column I5. The pipe 2S, nuts I!! and I I, cotter pin 3l, anchor plate 9, locking plate 32 and bolts 33 are similar to those parts as already described. The anchor rod 57 is threaded at both ends. The lower portion is firmly embedded in the concrete column I5. The upper threaded end is iitted with two nuts 59 and 6I, one being above the flange 53 and the other below it.

The adjustment of this anchorage is sirnple. If the tower is to be raised, the nut 53 loosened, the nut 6l is raised the desired anicup; (the tower leg IB moving up with it) and the nut 5S is retightened. If the leg I5 is to be lowered, the nut 6I is first lowered (the leg I6 mov- 5 ing down with it) and then the nut 59 is retightened.

It is to be noted that, in the embodiments of my invention described herein, the anchor rods 8 and 51 are rmly embedded in concrete for an appreciable portion of their length. A metal rod sustains a greater load per unit of cross-sectional area than concrete. In my anchorage the compression load is transmitted through the anchor rod into the concrete foundation column. This distribution of the load enables both the concrete column and the base plate resting upon it to be made smaller than with anchorages which do not transmit compression. Thus the use of my anchorage results in a considerable saving in material.

A formula for ascertaining the safe area of a concrete column is the following:

in square inches and P is the load in pounds. When a steel anchor rod under compression is used, the formula is as follows:

A P-75ooA where A5 is the area of the steel in square inches.

Thus, it is seen that the steel rod sustains a considerable portion of the load with a resultant reduction in the size of the steel base plate and the concrete foundation and a corresponding reduction in the labor necessary to construct the same.

Where the structure to be sustained has a considerable dead weight, a further economy of materials and labor may be accomplished. The anchor rods may be put into compression by delaying the grouting or other shimming until enough of the structure has been erected to obtain the desired load (P) upon said rods. After the grout has hardened the erection of the structure is completed. When so constructed, the formula will be:

When used for xed column bases of buildings which have to transmit axial loads and bending moments to the foundation, a considerable saving can also be effected by the use of my adjustable anchorages as they will transmit an increased part of the moment as well as a part of the axial load.

Although I have shown my invention in a vertical position, its use need not be limited thereto. I have shown preferred embodiments of my invention, but it is obvious that other uses as well as changes or omissions in structure may be made without departing from the spirit thereof.

I claim:

i. An adjustable anchorage anchoring a leg of a structure, comprising a concrete foundation; an elongated rod, embedded for part of its length in said foundation, the upper end of said rod being externally threaded; an elongated adjusting member, disposed conc-entrically with said rod; one end of said member terminating in a tubular, internally threaded portion, in threaded engagement with said iiternally threaded portion; means near the other end of said member to facilitate rotation of said member; a base plate sustained both -directly by the foundation and also indirectly by the foundation by way of the Il i) 6 member, the leg of the structure being sustained by said base plate; strap means loosely encircling said member and secured to said leg; and hold down means on said member to prevent said strap means from moving upward relative to said member.

2. An adjustable anchorage to position and sustain a structure, comprising a foundation, an elongated anchored member firmly embedded in said foundation for a portion of its length, an adjusting member in movable engagement with said anchored member, a base plate supporting said structure, shimming means positioned intermediate said base plate and said foundation, said base plate at all times being at least partly supported by said adjusting member whereby, upon operable movement of said adjusting member, the structure may be positioned relative to said foundation, and whereby, upon positioning of said shimming means, the structure rests upon the base plate and the structure and base plate are supported by said foundation partly through said shimming means and also partly through said anchored member.

3. A device adjustably sustaining a structure, including a foundation, a standard of adjustable length, an elongated portion of said standard being firmly embedded in said foundation, fastening means coupling said structure to said standard, shimming means positioned between said structure and said foundation to transmit compressive forcesfrom said structure to said foundation, whereby said structure is positionable relative to said foundation and compressive forces may be transmitted to the foundation from the structure through both said shimming means and said standard.

4. An adjustable anchorage sustaining a structure, comprising a foundation, a substantially vertically disposed anchor rod firmly embedded in the foundation for a portion of its length, shimming means positioned between said structure and said foundation to transmit compressive forces therebetween, adjusting means coupled to said structure and in threadable engagement with said anchor rod, whereby, upon rotation of said adjusting means and positioning of said shimming means, the structure may be moved substantially vertically relative to said foundation and compressive stresses may be transmitted to the foundation from the structure through both said anchor rod and said shimming means.

5. An apparatus adjustably sustaining and anchoring a leg of a structure, comprising a concrete foundation, an anchor firmly embedded in said foundation, an adjustable standard including an anchored member and an adjusting member' in threadable engagement with each other, said anchored member being firmly embedded in said foundation and secured to said anchor, said adjusting member having means for sustaining said leg, the threadable engagement between said members being adjustable to vary the length of said standard and to thereby move said leg to a plurality of positions relative to said foundation, a base plate sustaining said leg and in engagement with said standard and also with a relatively large area of said foundation, whereby said leg may be sustained and anchored at any of said positions and compressive stresses may be transmitted from said leg through said base plate directly to said foundation and also indirectly to said foundation through said standard.

5. An adjustable anchorage sustaining and anchoring a structure, comprising a foundation, grout-like material for raising, in effect, the height of said foundation, a standard of adjustable vertical length including an anchored member and an adjusting member, said anchored member being firmly embedded in and anchored to said foundation and sustained thereby, said adjusting member being in threadable engagement with said anchored member, means coupling the structure to said adjusting member, said last named means permitting rotation of said adjusting member during adjustment thereof, base plate means for transmitting compressive stresses from the structure to both a relatively large horizontal area of said grout-like material and to said standard.

7. An adjustable anchorage to position and sustain a structure, comprising a foundation, a layer of shimming material on top of said foundation, an elongated anchored member firmly embedded. in said foundation for at least a portion of its length, an adjusting member sustained by, and adjustable relative to, said anchored member, a base plate supported by said shimming material and saidl adjusting member and receiving the compressive forces from said structure, said structure being positionable relative to said foundation by adjustment of said adjusting member and, when so positioned, the compressive forces from said structure being transmitted partly through said base plate and shimming material to said foundation and partly through saidv base plate and anchored member to said foundation.

8. An adjustable anchorage sustaining a structure, comprising an elongated foundation, a transversely disposed layer of shimming material abutting one end of said foundation, a standard of adjustable length, said standard including an elongated portion firmly embedded longitudinally in said foundation, a transversely disposed base plate abutting said shimming material and said standard, said base plate being of large transverse cross sectional area and said elongated portion of relatively small transverse cross sectional area relative to the transverse cross sectional area of said foundation, whereby7 upon adjustment of said standard, the structure is positionable and, upon application of a proper thickness of shimming material, compressive forces are transmitted to the foundation from the structure through said base plate and shimming material and also through said base plate and standard.

9. An adjustable anchorage as defined in claim 8., wherein the foundation is of concrete, the shimming material is of grout and the elongated portion of the standard is of metal.

10. An adjustable anchorage sustaining structure relative to a foundation, comprising shimming means positioned intermediate the upper end of said foundation and said structure to, in effect, increase the length of said foundation; an anchor rmly embedded in said foundation, a substantially vertically-disposed elongated anchor rod securely attached to said anchor, the lower part of said rod being rmly embedded in said foundation, a portion of the upper part of said anchor rod being externally threaded; a shaft, said shaft having an internally-threaded portion in tbreadable engagement with the threaded portion of the anchor rod; a thrust bearing sustained by said shaft; a base plate sustainable partly by said thrust bearing and partly by said foundation as lengthened, in

effect, by said s himming means and, in turn, sustaining said structure; means to vary the threadable engagement between said shaft and said anchor rod; and means to secureA said shaft to said structure so as to lock said structure against upward movement; whereby said structure may be moved to various positions upon operation of the means to vary the threadable engagement, and said shimming means may be positioned to, in effect, lengthen said foundation and said structure may be sustained partly directly by said foundation as so lengthened, in effect, by said shimming means and partly indirectly by said foundation through said anchor rod and locked .against upward movement at any of said positions.

l1. An adjustable anchorage sustaining a structure, comprising a concrete foundation, shim means to, in effect, vary the height of said foundation, the structure resting on the shim means to permit the transmission from the structure to the shim means of compressive stresses, and a vertically elongated metal assembly secured to said structure, to permit the transmission from the structure to the assembly of both tensile and compressive stresses, and cohesively embedded for part of its length in, and anchored to, said foundation, said assembly including adjusting means to vary its eective length between the point of attachment to said structure and the anchorage of said cohesively embedded portion in the foundation so as to vary the position of said structure relative to. said foundation, tensile stresses, from said structure, being transmitted to said foundation through said metal assembly and compressive stresses, from said structure, being transmitted through said concrete foundation partly by way of said shim means and partly by way of said metal assembly, said metal assembly alone being capable of supporting said structure while its position is being varied.

l2. An anchorage supporting a structure, comprising anchor rod means and a foundation, said anchor rod means having greater compressive strength per unit of cross sectional area than said foundation, a portion of said anchor rod means being elongated and firmly embedded in said foundation, and said elongated portion being snugly gripped throughout its length by said foundation, said anchor rod being adjustable effective length, shim means to, in effect, extend the length of said foundation, said structure being coupled to said shim means and said anchor rod means, compressive forces being transmitted from said structure to said second means partially through said shim means and partially through said anchor rod means.

i3. An adjustable anchorage securing a structure against a substantially de. iward load which is transmitted through seid structure, comprising a concrete foundation; shim means above said foundation; a substantially vertically disposed elongated rod embedded for at least part of its length in said foundation, the upper end of said rod being externally threaded; a substantially vertically disposed rotatable elongated adjusting member, the lower end of said member being provided with an internally threaded sleeve, said sleeve being in threaded engagement with the threaded upper bearing means end, of the rod; sustained by said adjusting member, said bearing ineens boing vertically adjust ble, upon rotation of said member, while sustaining said substane` tallv downwardly directed load; and a base plate sustaining said load and transmitting it to both the shim means and the bearing, so that said downwardly directed load simultaneously transmits compressive stresses to the surface of the foundation by way of the shim means and also through the foundation by way of the bearing and rod.

14. An adjustable anchorage securing a structure against substantially upward and downward forces, comprising a concrete foundation; shim means above said foundation; a substantially vertically disposed elongated rod embedded for at least part of its length in said foundation, the upper end of said rod being externally threaded; a substantially vertically disposed rotatable elongated adjusting member, the lower end of said member being provided with an internally threaded sleeve, said sleeve being in threaded engagement with the threaded upper end of the rod; bearing means sustained by said adjusting member, said bearing means being vertically adjustable, upon rotation of said member, while said bearing is sustaining said substantially downwardly directed force from said structure; a base plate sustaining said substantially downwardly directed force and transmitting it to both the shim means and the bearing, so that said downwardly directed force may simultaneously trans- 10 mit compressive stresses both to the surface of the foundation by way of the shim means and also into the foundation by way of the bearing and rod; and hold down means attached to said adjusting member securing said structure against said substantially upwardly directed force so that said upwardly directed force transmits tensile stresses through said rod.

ERIC A. BLACK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Brown May 12, 1942 

